[DF / Magic] Pearl of Power: Guided Missile

[Tinman]

Originally Posted by Varyon

At my books now. Checking the rules from Thaumatology (I don't have Magical Styles, so things might work differently there), it looks like the Technique is per-skill (as typical for Techniques). If the pearl allows the character to add the effect to any relevant spell, without a penalty, I'd say that's a good case for a Wildcard Technique, increasing the initial cost to [34] ([1] for the Perk, [33] for the Technique).

So magical styles has the perk as one of 3 ways:
1) 1 specific enhancement per specific spell (guided/fireball)
2) 1 specific enhancement to any apilicable spell (spell enhancement: guided)
3) any enhancement to a specific spell (spell variation: fireball)

My item, I think, looks like #2 so I don't think it needs the wildcard technique.

[Plane]

One thing I like about Guided/Homing is it gives a means of making "requires multiple turns to reach more distant targets" spells, and situations where

1) people might easily avoid spells if they had multiple turns to get out of the way and knew it was coming

2) if the target can't move (perhaps unaware) more turns for allies who are aware to interpose themselves or prepare countermeasures. Ozma teleporting in front of the munchkins and then stopping Wilhelmina's spell in the recent "Return of the Silver Slippers" comes to mind, though I guess that might be possible with AOD:Double (sacrificial dodge + blocking spell)

[Tinman]

Originally Posted by Christopher R. Rice

Well, it's a little more complicated than a perk because of how Adjustable Spells work in GURPS.

First, you'd need to price this out as an ability using the rules in GURPS Thaumatology. That would be a perk (Rules Option) plus a technique to add Guided (a Spell Technique). Since Guided is a +50% enhancement that's going to add 10 FP to do it as well as as 11 points to buy the penalty off. Thus, that's a 12 point ability. Next, I would convert it over to an advantage so you can further modify it. Since you want it set at 1/day that's a -40% limitation or 8 points. I'd use the rules for signature gear ($500/point) to price it so the cost of it would be $4,000.

If you want the FP cost to go away, add Reduced Fatigue Cost to the base trait raising the cost to 32 points and worth $16,000.

That's kind of waggy, but it should be enough to get you in the right ball park.

Wow! I thought it would be a minor magic item. I'm looking to make it as cheap as possible & not cost the caster an extra 10 FP to cast.

That definitely gives me a proper answer, but I'd really like to make it cheaper.

For this application I don't think Varyon's gadget limitations would brake anything & I hope it will give the item the feel I'm looking for.

The discussion in this thread have really helped me out. Thanks.

If you guys have any other ideas as to how to implement the item or make it more of a "minor boon" type of item, please share them.

[Tinman]

Originally Posted by Christopher R. Rice

Sure, that's another way you could do it. You could apply One Stunt only (-50%) to the ER for cheaper, but that feels...like cheating.

Why cheating? Is it much different from say... an exclusive powerstone? (Magic p.70)

[Celjabba]

Originally Posted by Tinman

Wow! I thought it would be a minor magic item. I'm looking to make it as cheap as possible & not cost the caster an extra 10 FP to cast.

That definitely gives me a proper answer, but I'd really like to make it cheaper.

For this application I don't think Varyon's gadget limitations would brake anything & I hope it will give the item the feel I'm looking for.

The discussion in this thread have really helped me out. Thanks.

If you guys have any other ideas as to how to implement the item or make it more of a "minor boon" type of item, please share them.

This is the kind of situation that show why you may want to use multiplicative modifiers instead of additive ones. (Powers p102)

using additive modifiers :

base cost : 12
no fp cost : +200% of 12 : +24
limited use 1/day : -40% of 12 : -4

total 12-4+24 = [32]

the limited use : 1*day limitation, which is a severe one, only save you 4 points. Not worth it on a 36 points advantage.
even if you added gadget modifier and other limitations to the maximum of -80%, you would only save 12*.8 = 9 character point for a total cost of [27].


using multiplicative modifiers :

base cost : 12
no fp cost : +200% of 12 : +24
limited use 1/day : -40% of 36 : -14

total 12*300%*60% = [22]

the limited use : 1*day limitation now save you 14 points.
If you add gadget modifier and other limitations to the maximum of -80%, the cost become 12*3*.2 = [8]

Of course, you have to decide if you always use additive or multiplicative. And it is possible some builds would break using that optional rule. But it may be interesting to consider.

[Tinman]

Originally Posted by Celjabba

This is the kind of situation that show why you may want to use multiplicative modifiers instead of additive ones. (Powers p102)

using additive modifiers :

base cost : 12
no fp cost : +200% of 12 : +24
limited use 1/day : -40% of 12 : -4

total 12-4+24 = [32]

the limited use : 1*day limitation, which is a severe one, only save you 4 points. Not worth it on a 36 points advantage.
even if you added gadget modifier and other limitations to the maximum of -80%, you would only save 12*.8 = 9 character point for a total cost of [27].


using multiplicative modifiers :

base cost : 12
no fp cost : +200% of 12 : +24
limited use 1/day : -40% of 36 : -14

total 12*300%*60% = [22]

the limited use : 1*day limitation now save you 14 points.
If you add gadget modifier and other limitations to the maximum of -80%, the cost become 12*3*.2 = [8]

Of course, you have to decide if you always use additive or multiplicative. And it is possible some builds would break using that optional rule. But it may be interesting to consider.

That's a lot of savings. I've never used multiplicitive modifiers, always additive.
I find that powers tend to dominate in most of my games so I'm a little hesitant to make them cheaper. However, for this particular campaign, I might consider it.

[Varyon]

Originally Posted by Tinman

So magical styles has the perk as one of 3 ways:
1) 1 specific enhancement per specific spell (guided/fireball)
2) 1 specific enhancement to any apilicable spell (spell enhancement: guided)
3) any enhancement to a specific spell (spell variation: fireball)

My item, I think, looks like #2 so I don't think it needs the wildcard technique.

That sounds like it’s assuming a campaign were one where enhancing spells isn’t something you can just do; the Perk is thus a case of Extra Option, and you’d still need to buy the Technique separately for each spell, or use a Wildcard Technique. That said, I don’t think anything will break if you allow a single normally-priced Technique apply to all relevant spells. As noted above, using my Gadget Limitations and the like, that sets cost around $4500.

[Tinman]

Originally Posted by Varyon

That sounds like it’s assuming a campaign were one where enhancing spells isn’t something you can just do; the Perk is thus a case of Extra Option, and you’d still need to buy the Technique separately for each spell, or use a Wildcard Technique.

Yes, I figured that out from Christopher Rice's response.

That said, I don’t think anything will break if you allow a single normally-priced Technique apply to all relevant spells. As noted above, using my Gadget Limitations and the like, that sets cost around $4500.

I like the idea of adding gadget limitations to it.
$4,500 is much closer to my concept than $16,000.
In fact I'm pretty sure I'm going with it, as $4,500 should work just fine.

[Christopher R. Rice]

Awesome. Let us know how it works in game. :-)

[Tinman]

Originally Posted by Christopher R. Rice

Awesome. Let us know how it works in game. :-)

Thanks, I will.
It's a game I'm running for five of my friend's kids (13-14 yo) scattered around the country. They are all new to GURPS. It's over Skype & Maptools.
I'm not sure the wizard will get the best use out of it but I'm really excited by the concept.